Radiant in-floor heating systems typically utilize hot fluids circulating through tubes (hydronic systems) or electric current through cables (electrical resistance systems) installed in concrete slabs or attached to a subfloor and covered with a pourable floor underlayment. Hot fluids circulating through the tubes or electrical resistance in the cables warm the underlayment and the floor covering above.
These hydronic and electrical resistance systems, however, have the disadvantages of high capital and installation costs as well as the difficulty and high cost involved in maintenance and repair. For instance, electrical resistance systems typically include a plurality of heating cables disposed along a serpentine path and spaced above the top surface of the sub-floor. Such paths are customized based on the layout of the floor for which heating is desired. Once the cable is installed, cementitious slurry is then poured over the sub-floor to embed the resistance heating cable into the cement layer. In both cases, the heating elements are typically encased in a cement or gypsum slab. Once so encased, flooring is applied over the slab. Such systems significantly increase the time and labor required for construction.
To address the such shortcomings, efforts have been made to provide pre-assembled mats that incorporate electrical resistors (heating elements). Multiple such mats may be laid out to cover a floor or subfloor and interconnected (e.g., electrically connected). These mats are then secured to the floor or subfloor and may then be covered with cement/gypsum, tile and/or other flooring materials.